Not since the puff of white smoke heralding the election of Pope Benedict XVI just over a year ago has there been such important news from the Vatican: a study by its council for health pastoral care is about to recommend changing a fundamental precept of Roman Catholic law by permitting the use of condoms - though only in marriage and only when one of the partners has Aids.

Since the Pope, following the 1968 encyclical Humanae Vitae, has said that the use of condoms is "morally inadmissible" and advocates sexual abstinence as the best way to fight the spread of the virus, that would be a limited but significant change. It would also answer a burning question for some of the 165 million Catholics who live in Africa, a continent devastated by Aids. Theory may matter more than practice, since believers there, as elsewhere, tend to ignore silly advice.

Experts detect the influence of Cardinal Martini, Archbishop Emeritus of Milan, who says the use of condoms could be construed in certain situations as "a lesser evil" than death. But given the nature of Vatican politics, it is inconceivable that this carefully signalled reform does not have the blessing of the pope. That seems to be further proof of a liberal turn by the conservative who headed the department that once ran the Inquisition. Cardinal Ratzinger used to be called "God's Rottweiler", but bark and bite have been replaced by something more friendly and gentle. Pope Benedict is more of a dachshund these days.